Gilead Sciences, Inc., said on Friday additional data from a late-stage study showed its antiviral remdesivir significantly improved clinical recovery in severely ill COVID-19 patients.
Findings from an analysis of its late-stage study showed that 74.4 percent of remdesivir-treated patients recovered by day 14 versus 59 percent of patients receiving standard of care, the company said.
Dr. Scott Gottlieb, the former commissioner of the Food and Drug Administration, said in a tweet that the news “is very encouraging but needs to be confirmed in a prospective trial.”
Also this week, a new analysis of research on the drug shed some light on which patients fare better with the treatment.
The new data found the most benefit for severely ill patients under age 65, people who didn't require as much oxygen and those who hadn't received biologic treatments used to tackle an overzealous immune response called a cytokine storm. Black patients also seemed to do better than other groups. The findings, presented Thursday at a briefing ahead of the COVID-19 Conference at the AIDS 2020 Virtual Meeting, are further analysis of clinical trial results previously published in the New England Journal of Medicine.
"I think the question was who does well with remdesivir and who may need something else," the lead author of the study, Dr. Kristen Marks, an infectious disease specialist at Weill Cornell Medical Center, said in an interview.
While outcomes varied among ethnic groups — patients were white, Black, Asian and Hispanic or Latino — and regions, the data confirmed that remdesivir isn't as helpful for the sickest patients, Marks said.
In the clinical trial, hospitalized COVID-19 patients were randomly selected to receive intravenous remdesivir once a day for five or 10 days. There was no placebo group. The researchers found that a five-day treatment course was as safe and effective as a 10-day course, Marks said during the briefing Thursday.
After a median followup of 10 days, 256 patients had clinical improvement in oxygen support, and 44 had died. Patients over 65 and those who had histories of chronic obstructive pulmonary disease had higher risks of dying.
There are no plans to submit the data to a scientific journal.
The Weill Cornell conclusions didn't surprise Dr. Sarah George, an infectious disease specialist at Saint Louis University.
"It clearly shows as you would expect that the people who needed less oxygen and were of younger age did better. The people who are less sick are just likely to do better," said George, who is the lead investigator for the National Institutes of Health's remdesivir trial at Saint Louis University and wasn't involved with the new research.
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The small size of the analysis may be why Black patients seemed to do better, said Dr. Andre Kalil, an infectious disease expert at the University of Nebraska Medical Center in Omaha. Kalil, a principal investigator for the NIH's remdesivir trials, said he hadn’t observed similar results.
"You have to realize that only 44 people of the 397 people were Black, so just be cautious with that interpretation," Kalil said.
He also cautioned that the study didn't include a placebo group, and he said that given the sample size, people shouldn't over-interpret the results when looking at factors like age, region or ethnicity.
Remdesivir is one of the two most promising drugs to treat COVID-19 to have emerged so far. In early findings of a separate study, patients who received remdesivir had statistically significant faster times to recovery than those who received placebos. It isn't a cure for COVID-19.
Last month, the federal government announced that it had secured more than 500,000 treatment courses of the drug for American hospitals through September.
The drug is being tested to see whether patients do better when given a combination of remdesivir and barcitinib, a drug used to treat rheumatoid arthritis.